Meerkats are natural teachers—one of the few animals other than people so far shown to have the knack, say researchers.
Older hunters gradually introduce pups to the art of eating dinner before it runs away, reports Alex Thornton of the University of Cambridge in England. In the July 14 Science, he and his Cambridge colleague Katherine McAuliffe argue that these interactions meet the criteria for teaching.
“It’s really important to understand simple forms of teaching if we’re going to understand how human teaching evolved,” says Thornton.
The definition of teaching that Thornton and McAuliffe use requires that in the presence of pupils, the teacher does something special or performs a task less efficiently than it would on its own and that the pupils learn faster than they would without the teacher’s activity. Researchers previously argued that a British species of ant meets these criteria.
To test these ideas in meerkats, Thornton and McAuliffe worked with animal groups in the Kalahari Desert, including the animals now starring in the television series Meerkat Manor.
When pups first tag along with a foraging party, they’re “fairly incompetent,” says Thornton. They raise a racket of what he describes as “vaguely birdlike” begging calls (to listen to an audio file of these calls, click here).
The researchers tallied more than 2,000 instances in which an adult presented a pup with a lizard or other prey. For the youngest pups, 65 percent of those servings were alive, but for the oldest pups, almost 90 percent were still living.
The main cost to the adult forager is the chance that the fumbling youngster will let the meal escape, says Thornton.
While foraging, a meerkat often catches tidbits to give to youngsters that it doesn’t see but still hears. The researchers discovered that they could change the adults’ foraging behavior by broadcasting different pup calls.
When researchers played the begging calls of nearly grown pups to a meerkat group out hunting with newbies, the foragers increased the proportion of prey left alive for delivery. When researchers played the squeaks of young pups to groups with older tagalongs, the adult foragers upped the proportion of killed prey.
To check the benefits to the pups, the researchers gave some a series of live, stingless scorpions and others equivalent dinners of hard-boiled eggs. After 3 days, all the youngsters who’d received live scorpions managed to subdue a newly presented live scorpion. Two-thirds of the hard-boiled–egg crowd, however, let the scorpions escape. The difference, say the researchers, shows that the tutoring works.
Tim Caro of the University of California, Davis, one of the theorists who defined teaching, calls the new experiments “clever” and agrees that they satisfy the criteria in his definition of teaching.
Says Dario Maestripieri of the University of Chicago, who has studied teaching among macaques, “I’m sure there are a lot of interactions like this out there that people haven’t looked at.”